Endocardial electrode

ABSTRACT

An endocardial electrode for effecting the intracardial stimulation of a heart, consisting of an elongated electrical conductor, which is provided with an electrical insulation, and an electrode head located at the end of the conductor proximate the heart for the transmission of stimulative impulses to the heart through the inserted electrode. The surface of the electrode head is constituted partly of an insulating material, and partly of an electrically conductive contact material which is electrically connected with the conductor.



1. Endocardial electrode for the intracardial stimulation of a heart, comprising an elongate electrical conductor; an electrical insulation encasing said conductor; and an electrode head being connected to said conductor at the end thereof proximate the heart for transmission of stimulative impulses to the heart upon insertion of said electrode, said electrode head having a surface area the major portion of which is constituted of an insulating material and the relatively smaller remaining surface area of an electrically conductive contact material forming a plurality of spaced electrically conductive minute surface areas, each of saiD last-mentioned areas being electrically connected with said conductor.
 2. Endocardial electrode as claimed in claim 1, the surface of said electrode head having a maximum area of 15 mm2.
 3. Endocardial electrode as claimed in claim 2, said surface area being 5 mm2.
 4. Endocardial electrode as claimed in claim 1, said electrically conductive contact material being evenly distributed about the surface of said electrode head.
 5. Endocardial electrode as claimed in claim 4, said contact material being in the form of strips extending along the surface of said electrode head.
 6. Endocardial electrode as claimed in claim 4, said contact material being in the form of strips helically wound about the surface of said electrode head.
 7. Endocardial electrode as claimed in claim 4, said contact material comprising a plurality of discrete dot-shaped areas dispersed about the surface of said electrode head.
 8. Endocardial electrode as claimed in claim 1, said electrode head being of relatively large volume and weight, said volume being in the range of 15 mm3 to 60 mm3, and said weight being in the range of 0.30 p to 2.0 p.
 9. Endocardial electrode as claimed in claim 8, said electrode head having a volume of 25 mm3 and a weight of 0.8 p.
 10. Endocardial electrode as claimed in claim 1, said electrode head being essentially cylindrically shaped, said electrical conductor being fastened to one end of said cylindrically shaped electrode head, and the free end of said electrode head being of a rounded off configuration.
 11. Endocardial electrode as claimed in claim 10, said contact material being constituted of a band-shaped material.
 12. Endocardial electrode as claimed in claim 11, said band-shaped contact material being positioned in parallel spaced strips extending along the longitudinal axis of said cylindrically shaped electrode head.
 13. Endocardial electrode as claimed in claim 12, the space between adjacent strips of said contact material being 0.5 mm to 5 mm wide.
 14. Endocardial electrode as claimed in claim 13, said space between adjacent strips of said contact material being about 1.5 mm wide.
 15. Endocardial electrode as claimed in claim 11, said band-shaped contact material being helically wound to form a plurality of spaced strips extending about the annular surface of said cylindrically shaped electrode head.
 16. Endocardial electrode as claimed in claim 15, the space between adjacent helically wound strips of said contact material being about 0.5 mm to 5 mm wide.
 17. Endocardial electrode as claimed in claim 16, said space between adjacent helically wound strips of said contact material being about 1.5 mm wide.
 18. Endocardial electrode as claimed in claim 11, said band-shaped material having a width in the range of 0.01 mm and 0.4 mm.
 19. Endocardial electrode as claimed in claim 14, said band-shaped material having a width of about 2 mm.
 20. Endocardial electrode as claimed in claim 1, said electrode head comprising an electrically conductive material core having projecting portions forming interstitial spaces; and an electrically insulating material being filled in said interstitial spaces.
 21. Endocardial electrode as claimed in claim 20, said projecting portions being essentially ridge-like in configuration.
 22. Endocardial electrode as claimed in claim 20, said projecting portions having a helical screw-thread configuration.
 23. Endocardial electrode as claimed in claim 1, said electrode head being formed of an electrically conductive basket-shaped wire mesh; and electrically insulating material filling the interior of said basket shape and wire mesh interstices.
 24. Endocardial electrode as claimed in claim 23, said insulating material having a relatively high specific weight. 